


When You’re A Fish

by Cyan_Sky1



Category: The Amazing World of Gumball
Genre: Biting and ear pulling, Cunnilingus, Don’t read this if you haven’t watched The Orgins first, Kinda, Love Confessions, M/M, Oh Penny you naive bastard, Part 1 of Wishes Do Come True, Parties, Sensitive Ears, Some Fluff, Some Humor, Some angst, Some cliche stuff, THE BOYS ARE 16-18 IN THIS I FORGOT TO MENTION, Underage Drinking, Vaginal Fingering, Vaginal Sex, wowsers ‘bout damn time I post a smut fic on here
Language: English
Status: In-Progress
Published: 2018-05-24
Updated: 2018-05-24
Packaged: 2019-05-13 04:20:46
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 3,278
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14741891
Author URL: https://archiveofourown.org/users/Cyan_Sky1/pseuds/Cyan_Sky1
Summary: Gumball feels guilt and regret when Darwin starts avoiding him for unknown reasons, and tries to go to a party with him to get him to hang out with him again. But after he doesn’t go, he’s left alone with even sadder thoughts instead. Penny saves the day and things take an unexpected turn for the two ‘brothers’





	When You’re A Fish

**Author's Note:**

> Hey y’all I have a confession to make: I do actually write smut. Only it’s all mainly on a whim and it’s almost never finished. This is one of the few that I actually did finish and actually wanted to post on here. So enjoy! Please note if you haven’t watched the Gumball episode The Origins then you won’t get some of the references made on here.

The music is making his head pound.

His whiskers are twitching out of irritation.

And he’s longing for his brother.

Not just the normal longing, either. It’s a ‘If I don’t see him within the next five minutes I’m going to jump out the window and find him on all fours’ type of longing. 

As in, Gumball is going to do just that if he doesn’t see his brother soon. 

Which he knows is super bad, because this party is supposed to last for another hour. And he’s already been here for two.

At first it wasn’t all that bad. He danced with his girlfriend, his other-well I guess you can call them friends-were talking to him and keeping him in good spirits, and the music-at first-was super good.

Until he made his mistakes.

His first mistake was having his first drink.

His second mistake was having the next drink.

His third mistake was having another drink after that.

Following that analogy, Gumball has made a total of six mistakes now, and he was halfway through his seventh one when Penny finally found him.

“Gumball! Where have you been, I’ve been looking for you for the last half hour! Don’t tell me you’ve been here drinking the whole time!”  
“Oh...uh....” Gumball trailed off with no clue on what to say, but Penny’s face spoke plenty of words for the both of them.  
“What’s wrong?” Of course Penny would let the anger parts of her face go for now, and let the worry take the rest of her facial features when she saw the sorrow in Gumball’s eyes. That’s just how Penny works.

Gumball usually loves it, but right now he loathes it.

He hates that she was able to read him this quickly.

“M’fine.” The blue cat tried to speak but his words slurred together a little bit. Man, these mistakes of his are really starting to mess him up.  
“No, you’re not. You look like you found out the world is gonna end in the next hour and you’re trying to drink the sadness away. What’s going on?” Penny stopped floating and sat in the seat next to Gumball.

The blue cat furrowed his brows a little bit while trying to think of a response. 

To be perfectly frank, he’s not quite sure why he feels so upset in the first place. All he knows is he wants to see Darwin. Badly. But is that really all that’s up? He knows there’s something more to it. No, he feels guilt. Like he’s done something wrong. 

“I think Darwin’s mad a’me.” Gumball tried to put his feelings into words, “But I don’want him to be. I miss ‘em.”  
“Why do you think he’s mad at you?” Penny leaned forward slightly with a look of interest in her eyes.  
“He’s been avoidn’ me all week. I dunno why an’ I tried to tell ‘em to go to dis party wh’ me buh he didn’t wanna. So I.....feel....” Gumball trailed off, not wanting to say it.  
“Alone?”  
“Mhm.” He made a noise of agreement and nodded his head slightly when Penny said it for him.  
“It sounds to me like you’ve been trying to talk to him but he’s been pushing you away ever since he’s started avoiding you. And you’re trying to give him the space he needs but it’s really difficult for you because you don’t want him to avoid you. And you tried to invite him to this party as a peace offering but he refused, so now you’re trying to forget about how you feel and it’s failing miserably so you’re trying to drink them away.” Penny concluded with so much ease it made Gumball feel like his emotions were the most simplest thing in the world. 

It kinda hurt.

“I say you need to go to him asap. While it is sweet you’re trying to respect his wishes, it isn’t right for him to just suddenly start to avoid you like this. He could have at least given you a reason why first. So go home and talk to him.” Penny shrugged and smiled.  
“But....you invited m’here. Don’ you want me with ya?”  
“Gumball, That should be the least of your worries.” Penny puts a hand on his shoulder, “This is just a party. It’s no big deal. You figuring out your problem with your brother is much more important than being here for me. Family comes first, right?”

Brother. For some reason, that words doesn’t feel right to describe Darwin and his relationship anymore.

“Oh no, you’re starting to think hard again, I can tell. It takes quite the toll on your face.” Penny moves the hand from his shoulder and puts her hand on his cheek.  
“Just go on already. I’ll survive.” Penny smiles and it’s so nice and bright that it makes Gumball’s heart leap to his throat.

Penny’s right. He’ll have to decide on what his emotions are telling him later, now is time for action.

Gumball(almost) gets exactly what he wanted to do and runs out the door on all fours, ignoring the blurred lines in the edges of his vision and the occasional unintentional sway of his balance.

—-

Thank god Anais was at a sleepover, Nicole was away on a business trip, and Richard is the equivalent to a dead rock glued to the couch when he’s asleep on the actual couch. Otherwise Gumball would’ve panicked when he came into the house with heavily flushed cheeks, his fur a mess, and very obviously drunk. 

He still checks around the house anyway, to make sure no one else other than Darwin and Richard was home. Luckily, everyone is still at their said place. The cat sighed in relief before carefully making his way upstairs. He slowly and quietly opens the door to Darwin and his room, but was hit with something he has never felt before.

Pure desire.

He smelled something sweet, something sweeter than he’s ever smelt before. Better than a million cupcakes. And Darwin was right there on his bed, his back to him but still very obviously flushed and slightly sweaty, and messing with something between his legs. 

Wait, something is between his legs?!

“Wha-?! DARWIN YOU HAVE A-“  
“AAA!” The poor frightened goldfish screamed and fell off the bed while trying to turn to Gumball, landing on the carpet with a loud thump.  
“Darwin!” Gumball rushed to check on his best friend, but stopped dead in his tracks at what he saw. 

He knows that gleam in his eyes from anywhere.

Darwin was in heat.

“How...why...I thought you were just a regular goldfish? You can...you have heats...?”  
“Erm...uh...” the teenage goldfish was very clearly not expecting for all of this to happen this quickly or this suddenly, but he did know he owed Gumball some answers. He makes sure he moves his legs at a angle to where he can’t see what’s between them before answering.  
“Just...come and sit on the bed with me, and I’ll tell you everything.” Darwin stands up by himself, and perches himself on the same spot on the bed he originally was. Mostly to hide the small...wet spot there.

Gumball compiles and sits next to Darwin, but quickly scoots back a few inches after remembering the enticing smell the goldfish was emitting.

“Remember how we’re connected?”  
“Yeah, of course I do.” The blue cat instinctively brings his paw to his heart.  
“Well. I figured out that whenever you wish for something that involves any sort of body part, your wish brings me a new body part I’ve never had before.” Darwin shifts nervously in his spot, “But some parts are still very different from yours, because I’m still a fish. And see, when you’re a fish...some parts are just out of your control.”  
“Out of your control?” Gumball echoed, very clearly not getting where Darwin was going with this.  
“You see...goldfish has different...mating rituals then other animals. We can change our sex. But originally mine was barely there, not even a thing to worry about. But then...you wished something...and it caused...much more different parts than I’d originally had. It’s more...like the other animals around here. More...functional.” The goldfish fidgets with his hands in his lap, “But my sex can still change. And recently, I’ve been feeling...much more sensitive to touch. More feverish. More...everything. I did some research on my own and found out I’ve developed a heat cycle because of your wish.”  
“My wish. You mean...oh god.” Gumball slaps his paw over his mouth when he realized what Darwin was talking about.

A long time ago, Gumball was playing with himself...he wished he had someone to fuck.

Oh.

Shit.

“I did this to you.” Gumball’s eyes watered up, and he very suddenly gave Darwin a hug.

Normally, Darwin would love and greatly enjoy the hug...but now it’s very close to a certain area...

“G-Gumball....you’re kinda...”  
“O-Oh, sorry, sorry!” The blue cat scooted away from him again and went back to his original spot.  
“And it’s ok. I know you didn’t mean to do that. Wishes take form in weird ways, y’know?” The goldfish beamed, but then hesitated to blush, remembering what was causing their problems in the first place when he felt a wave of heat hit him again. Gumball noticed that Darwin’s scent became stronger, and his faced flushed a deep shade of red.

“Hey...since I caused this mess, do you...do you want me to help?”  
“Hey, this mess isn’t entirely your fault!” Darwin stopped to look at the cat in the eyes, “I avoided you without telling you what was going on, and that’s why you walked in on me in the first place, so you don’t have to do anything that you don’t want to-“

“No, I want to.” 

The words flew out of his mouth before he could even think about it, which caused both of the boys to flush a bright red.  
“W-Well...if you really want to...”

Darwin looked down at the floor while shifting his body to face Gumball’s, and lifted his legs just enough for the blue cat to see what was going on between his legs.

Sure enough, there was a nice, neat vagina, and it looked slightly puffy and wet due to his arousal. It looked plump and juicy, and perfect. Gumball felt like he couldn’t get closer to it fast enough, but to Darwin it felt like 2.5 seconds passed before he was pinned to the bed. 

“W-Wait.” The goldfish stopped the cat before he could do anything.  
“Yeah?”  
“Get on your knees on the side of the bed, and I’ll sit on the edge. It’ll be...easier that way, I think.” Darwin licks his lips nervously, but Gumball nodded his head at his request.

He took the next minute to shift in a comfortable position on his knees on the floor, and let his best friend put his legs on either side of his torso to keep himself wide open to him. Gumball looked down again to see his pussy before slowly moving a finger to rub across it slightly, earning him a shiver.

“So, you have a pussy right now, but can you form a dick?”  
“N-no I can’t. My sex changes on its own based on my heats and whenever I get aroused I think. I can’t control it.”  
“So you hid this pretty little thing between your legs without putting any shorts on it or anything?” Gumball went to give a practice lick after finishing his sentence, which made the goldfish let out a little sigh.  
“It only appears when I’m aroused or in heat, otherwise I just have normal goldfish parts. Which compared to this and my dick, is microscopic.” Darwin let out a little breathless laugh, but chocked on it when the blue cat went for a longer stroke of his tongue across his folds.  
“Makes sense.”  
Gumball starts to really lick into his slit now, gripping both of his thighs with his paws for leverage as he went deeper in.  
“G-Gumbaahh...” Darwin tries to speak, but trails off with a moan. 

He knew things like this were supposed to feel good, but never like this. His head feels like it’s swimming in pleasure, and all he can think about is the beautiful tongue in between his legs. The teenage cat moves his tongue up from his slit to try to lick at his clit, which causes an even deeper wave of pleasure to shoot tingles through his body. Darwin wraps his legs around Gumball’s back and hugs his head closer to his. His breath starts to come out in panting breaths that tickle the cat’s ears.

“D-Darwin..!” Gumball stops his licking to release a small moan of his own.  
“Be c-careful. My ears are really...sensitive.”  
“Oh?” Said fish looks down at his counterpart, and smirks mischievously.  
“It’s only fair I help you feel as good as I do right now.” And with that, Darwin starts to kiss and lick at Gumball’s ears, which sends a heavy shiver down his spine.  
“D-Dude I...uh~!” The blue cat smashes his face back into Darwin’s pussy and licks it with renewed vigor, trying to lick into it as deep as he could.

The boys settle into a rhythm. For every lick, kiss or movement of Gumball’s tongue, Darwin would return it with a bite, lick, or kiss of his own on the blue cat’s ears. Gumball quickly learns that licking Darwin’s slit or sticking his tongue inside of it earns him licks and kisses to his ears, but when he licks his clit he gets bites and even occasional sucks on his ears. He finds himself wanting more of the ladder, so he sticks his finger into his pussy, careful to not release his claw in it, and started sucking on the clit too. Darwin at first just gives a loud sigh, but then starts to quiver with the pleasure when Gumball wiggles his finger and presses his tongue down on the clit at the same time. Darwin starts to lick the inside of Gumball’s ear, and that’s when he starts to really get affected.  
His body begins to tremble all over and he feels like his knees are gonna buckle under him. He can’t go on like this.

“D-Dah.....Darwin...!” Gumball pushes two fingers into said fish’s folds whole looking up at him, hoping putting two fingers in would make up for him stopping his licking to talk to him. “Please, I...I need you to treat them more roughly then that. Bite them harder, tug on them, don’t hold back. I’ll do the same for you.” The goldfish just nods his head in understanding, and returns to his ears with newfound motovation. He does exactly what Gumball requested, and starts to pull on one gently while biting down on the other one.  
“Hnnn shit I...I....Oh!” Gumball starts to fuck Darwin with his fingers, using his other hand to palm at his dick through his jeans. He returns to licking at Darwin’s clit with even more passion, licking and sucking on it like his life depends on it.  
“Oh god...Gumball I’m close!” Said cat nods eagerly, and uses the hand that he was previously rubbing himself with to point at his ears, as a sign he wants him to treat them even rougher, and the goldfish gets the message loud and clear. 

Gumball starts to add a third finger in and stretch out Darwin’s walls even wider, while licking his clit really fast and deep, meanwhile Darwin alternates between both ears to pull and bite them. The gold fish screams as he cums in Gumball’s mouth, and said cat makes sure to lick every last bit of it up.  
“Darwin I...” Gumball looks up at Darwin again to talk to him, “Do you think you can go again? I really, really need you. I can’t cum with only stimulation to my ears.”  
“I-I was just about to ask you that.” He eagerly nods in agreement to Gumball’s words, and scoots backwards on the bed so he get on it.

As soon as the two boys are on the bed the blue cat takes off his sweater and throws it across the room, then quickly does the same to his pants. When he’s left with only his boxers on, Gumball stops to look at Darwin.

“A-Are you sure you want me?”  
“Yes, god yes. Don’t be scared, Gumball. It’s only me.” Darwin reaches forward to touch his hand, which makes the cat’s heart flutter. He gives a single nod then reaches down to take off his boxers. After they landed on the floor, Darwin looks down and gulps. Puberty sure did make his dick way more larger then he expected. The goldfish bites his lip and blushes again, and a wave of heat hits him again.  
“Please, Gumball...I need you now.”  
“W-Wait, don’t we need a-“  
“I’m pretty sure your wish was to fuck me, not have kids with me.” Darwin gives Gumball another lustful grin, “I don’t think we need to worry about that.”  
“O-ok.” Gumball puts his arms on either side of Darwin’s body, then reaches down to guide his dick into his pussy.

It fits like a glove.

After that the boys could only remember pure, unrelenting pleasure and lust from that point on. At one point they remember that Gumball went on his knees again and lifted Darwin up to fuck him even deeper, and Darwin could only wrap his legs around him again and put his hands on his shoulders in response. 

Love, they were both filled with so much love.

It’s so much deeper then either of them thought it could be.

And they couldn’t deny it any longer.

They were connected, heart and soul to heart and soul.

And it was beautiful.

—-

The boys woke up the next morning covered in cum and tangled into each other. 

“Gumball...”  
“Yeah?”  
“What...what are we?”  
“Whatever we want to be. I don’t care.” The blue cat hugged the goldfish even closer to his chest, and purred while flicking his tail.  
“But what about Carrie, and Penny?”  
“I don’t think either of them would care. We could even go poly if we all really want to.”  
“Do you really think they wouldn’t care?”  
“Darwin, they saw us kiss in the treehouse, remember?”  
“That was ages ago!” The goldfish’s cheeks flushed at the memory.  
“Heh, still. I think they’ll accept us. I think everyone will accept us. We’re still ourselves, just closer. There’s really no need to panic.”  
“But...we’re brothers, remember?”  
“Not technically. But that doesn’t mean we can’t care for each other as deeply as we do still. Even more now. Our relationship doesn’t have to be strictly brotherly if we don’t want it to be. After all, you’re still my goldfish. Just with legs and a beautiful pus-“  
“Hehehe, I get it!” Darwin playfully shoves Gumball away from him and the cat laughs in response.  
“Ok. If you want us to be something more, than I’m up for it. I’ll do anything you want me to, Gumball.”  
“Hm~” Gumball hums in response and brings Darwin close again.  
“I think that’s what I needed to hear, Darwin. I feel so much better now. Thank you.”  
“You’re welcome!” The goldfish replied cheerfully, But was still slightly confused at what the cat was talking about. He’ll ask him about it later. 

 

“We should get into the shower now.”  
“Yeah, we should.”

**Author's Note:**

> P.S. I actually came up with this fanfic idea while taking a math test wtf is wrong with me


End file.
